Rotary cutting tools are useful for cutting thin material such as, for example, paper, paperboard, cardboard, plastic film, metal foil, thin sheet metal, etc. Generally a stream of paperboard or other thin material is fed between a pair of rotating cylinders. The thin material may be received on a large roll and then fed between the rotating dies. The cylinders have cutting surfaces which cut the thin material as it streams between the cylinders, allowing for high volume production of cut blanks. Rotary cutting tools include solid rotary dies, where the cutting surface is made part of the cylinders, and flexible rotary dies, where a die plate is wrapped around a cylinder.
It is important that the die plates of flexible dies be properly affixed to the cylinder and aligned, both with respect to the cylinder and with respect to each other. This is especially important given the speed of rotation of the die cylinders associated with high volume production. Known techniques for affixing and aligning the die plates include forming the die plate and die cylinders out of a magnetic material so that they are magnetically attracted to one another. However, such a design greatly increases the costs of the die cylinders.
U.S. patent application Ser. No. 10/730,580, assigned to the assignee of the present application, discloses a highly advantageous design for a rotary cutting tool where eccentrics are used for position adjustment of the die plate. It would be highly desirable to provide a rotary tool having an improved retaining and adjustment mechanism for use with eccentric position adjustment.